<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<html>
<head>
<!-- Copyright 1997 The Open Group, All Rights Reserved -->

<title>overlay</title>
</head><body bgcolor=white>
<center>
<font size=2>
The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

</font></center><hr size=2 noshade>
<h4><a name = "tag_001_009_710">&nbsp;</a>NAME</h4><blockquote>
overlay, overwrite - copy overlapped windows
</blockquote><h4><a name = "tag_001_009_711">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

#include &lt;<a href="curses.h.html">curses.h</a>&gt;

int overlay(const WINDOW *<i>srcwin</i>, WINDOW *<i>dstwin</i>);

int overwrite(const WINDOW *<i>srcwin</i>, WINDOW *<i>dstwin</i>);
</code>
</pre>
</blockquote><h4><a name = "tag_001_009_712">&nbsp;</a>DESCRIPTION</h4><blockquote>
The
<i>overlay()</i>
and
<i>overwrite()</i>
functions overlay <i>srcwin</i> on top of <i>dstwin</i>.  The <i>scrwin</i> and
<i>dstwin</i> arguments need not be the same size; only text where the two
windows overlap is copied.
<p>
The
<i>overwrite()</i>
function copies characters as though a sequence of
<i><a href="win_wch.html">win_wch()</a></i>
and
<i><a href="wadd_wch.html">wadd_wch()</a></i>
were performed with the destination window's attributes and background
attributes cleared.
<p>
The
<i>overlay()</i>
function does the same thing, except that, whenever a character to be copied
is the background character of the source window,
<i>overlay()</i>
does not copy the character but merely moves the destination cursor the width
of the source background character.
<p>
If any portion of the overlaying window border is not the first column of
a multi-column character then all the column positions will be replaced with
the background character and rendition before the overlay is done. If the
default background character is a multi-column character when this occurs,
then these functions fail.
</blockquote><h4><a name = "tag_001_009_713">&nbsp;</a>RETURN VALUE</h4><blockquote>
Upon successful completion, these functions return OK.  Otherwise, they return
ERR.
</blockquote><h4><a name = "tag_001_009_714">&nbsp;</a>ERRORS</h4><blockquote>
No errors are defined.
</blockquote><h4><a name = "tag_001_009_715">&nbsp;</a>SEE ALSO</h4><blockquote>
<i><a href="copywin.html">copywin()</a></i>,
<i><a href="curses.h.html">&lt;curses.h&gt;</a></i>.
</blockquote><hr size=2 noshade>
<center><font size=2>
UNIX &reg; is a registered Trademark of The Open Group.<br>
Copyright &copy; 1997 The Open Group
<br> [ <a href="../index.html">Main Index</a> | <a href="../xshix.html">XSH</a> | <a href="../xcuix.html">XCU</a> | <a href="../xbdix.html">XBD</a> | <a href="../cursesix.html">XCURSES</a> | <a href="../xnsix.html">XNS</a> ]

</font></center><hr size=2 noshade>
</body></html>
